1,2-propanediol, also known as propylene glycol, is commonly included in a variety of food products. The U.S. Food and Drug Administration has classified propylene glycol as “generally recognized as safe” (GRAS) for use as a food additive. Propylene glycol is used for many purposes, including, but not limited to, as a solvent for flavorings and food colorings that are not readily soluble in water. Propylene glycol is often used as a solvent in flavorings that are used to provide flavor to a variety of food products, including flavored beverages.
Propylene glycol is also commonly used as a humectant, preservative, or stabilizer. For example, propylene glycol is used as a humectant to promote moisture retention in products like chewing gum and candy. Propylene glycol is also included in various food products to reduce the water activity of the product, thereby acting as an antimicrobial and functioning to increase shelf life of the product. Propylene glycol is also commonly used as a thickening agent in food products like ice cream and yogurt.
The use of propylene glycol is often limited by the flavor imparted by propylene glycol to the food or beverage product to which it is included. In many applications, propylene glycol is perceived by consumers as contributing an undesirable artificial flavor to the food or beverage.
Propylene glycol is structurally very similar to a variety of other compounds, including glycerol. Glycerol is often touted as being a natural alternative to propylene glycol. Glycerol is a byproduct of biodiesel production and, like propylene glycol, can be included in various food products as a humectant, solvent, filler, preservative, and thickening agent. Use of glycerol in food products can be limited by the sweet taste provided by glycerol.
Further, there has recently been an interest in using food ingredients that are perceived by consumers as being natural ingredients. Therefore, alternatives to propylene glycol would be desirable for use in food and beverage products.